Turn your smartphone into a professional dyno. Measure your car's real HP & torque within 2% of a chassis dynamometer. Compare upgrades, track results. No OBD needed.
Know your car's true performance.
Turn your smartphone into a professional dyno. Measure the real horsepower and torque of your engine — within 2% of a chassis dynamometer — and time your car's acceleration. No OBD adapter, no cables, no expensive dyno sessions. Just mount your phone, accelerate, and get instant results.
Test and compare performance upgrades. Whether you're verifying an ECU remap, testing a new exhaust, or tracking the effect of a chiptuning session, PerfExpert gives you objective, independent data you can trust.
HOW IT WORKS
Create your car profile
Enter your vehicle's weight, tire sizes, and gear ratios. Not sure about a spec? The app guides you through every step.
Mount your phone & accelerate
Secure your phone in the car — no connection needed. Find a flat, straight road. Accelerate in one gear from low RPM to redline. That's it.
Get instant results
Power and torque curves appear immediately, just like on a real chassis dynamometer. Compare runs, track your modifications, and share results.
MEASUREMENT MODES
Dyno — Full power & torque curves vs. engine RPM. Advanced drivetrain loss model, rev limiter detection, and correction standards (DIN, SAE, JIS, CEE, ISO). Results as detailed as a professional chassis dyno.
Timed Run — Measure acceleration from a standing start. Speed intervals: 0-100, 100-200, 80-180, 60-160 km/h — 0-60, 60-120, 50-110, 40-100 mph. Distance: quarter mile, eighth mile (with trap speed), 60 ft. Max speed and peak acceleration on every run.
KEY FEATURES
2% accuracy compared to professional chassis dynamometers
No OBD adapter or connection to your car required
Works with your phone's built-in sensors
External GPS available as an in-app purchase for pro-level precision with a compatible device (RaceBox Mini, Mini S, Micro): rolling start dyno, free phone mounting
Power correction norms: DIN, SAE, JIS, CEE, ISO — using real-time atmospheric pressure, temperature, and humidity
Interactive charts: pinch to zoom, tap for exact values
Export results as PNG image or shareable web link
Custom units: HP, CV, kW for power — Nm, ft-lb, mkg for torque — km/h, mph for speed
Works on phones and tablets
PERFEXPERT PRO (optional subscription)
Custom logo on your results
Cloud backup of your results
CSV data export
WHO USES PERFEXPERT?
Car enthusiasts who want to know their real HP and torque
Tuners and mechanics verifying ECU remaps, chiptuning, intake, exhaust, or turbo upgrades
Owners comparing before/after results of any modification
Drivers timing their 0-60 mph or 0-100 km/h acceleration
Anyone curious about their car's true performance
IMPORTANT NOTES
Dyno mode requires a manual gearbox or an automatic with manual/sequential mode
For best results, use a flat, straight, horizontal road with no traffic
External GPS (in-app purchase) unlocks additional features with a compatible device (RaceBox Mini, Mini S, Micro): more reliable results, rolling start dyno (no need to stop before measuring), and free phone orientation
PerfExpert offers a cost-effective, visualization-driven way to estimate power and tune performance. Reviewers note accurate estimates when data is correct and useful graphs for tuning, but effectiveness is limited by vehicle coverage, data accuracy, and occasional reliability problems. When data aligns with the vehicle, many users view it as a credible DIY alternative to dyno testing.
Pros
Accurate horsepower estimates when correct vehicle data is entered (often within +/-5 HP).
Clear graphs and visualization that help you visualize power gains and tuning progress.
Cost-effective DIY approach that can negate the need for expensive dyno runs.
Often provides results that compare favorably to dynos in certain scenarios.
Cons
Limited vehicle coverage; not all cars are in the database, requiring manual data entry or exclusion.
Results are highly sensitive to input data (gear ratios, fuel type, drivetrain); wrong or missing data can lead to large inaccuracies.
Some users report reliability issues, including instances where the app does not work.
Recent reviews
Once I go through the calibration routine, it gives me no choice to move onto a test-only a “back” button that takes me back to the “calibration” button, forcing me to start over, in a circle. What may I be doing wrong?
byVi*****, 2023-06-21
If you get all the parameters right, it’s accurate to +- 5 HP. This app worked so well for me and helped me visualize and tune power gains for my old 86 300ZX, recently turbocharged.